1. Field of the Invention
The present invention relates to a tactile sensor device for sensing contact of a contacting member, such as a finger of a robot hand, with an object.
2. Description of the Prior Art
Robot hands for gripping objects and holding them while they are being worked on have fingers equipped with tactile sensors for sensing the presence and absence of contact of the fingers with an object and the magnitude of the pressure on the fingers in order to adjust the grip force with which the fingers grip the object and also adjust the position of the robot hand with respect to the object.
One generally known tactile sensor comprises a strainable member attached to a robot hand finger for contacting an object and a strain gage mounted on the strainable member. The force of contact between the robot hand finger and the object is detected on the basis of an output signal from the strain gage.
However, the conventional tactile sensor is incapable of stably detecting the force of contact between the robot hand finger and the object under various environmental conditions because the strain gage are liable to suffer characteristic variations due to temperature changes and susceptible to noise.
Strain gages are relatively easily subject to wire disconnections when shocks are applied thereto, need skilled labor and time in order to be installed in place and thereafter processed for output adjustments, and are expensive to manufacture.